Why are lymphocyte counts low after radiation therapy?

   Low lymphocyte count after radiotherapy may result from damage to lymphocytes, which is one of the adverse effects of radiation therapy. It could also be caused by medications such as glucocorticoids used during treatment. Additionally, endocrine disorders or immune system dysregulation may lead to this condition.

   1. Adverse effects of radiotherapy

   Within the body, lymphocytes are the primary immune cells, and T cells, B cells, and NK cells play extensive roles in various immune responses. During radiotherapy, X-rays, gamma rays, and other forms of radiation can affect the proliferation and differentiation of hematopoietic stem cells in the bone marrow, leading to a reduction in lymphocyte counts.

   2. Use of glucocorticoids and other drugs

   If glucocorticoids such as prednisone are administered during treatment, severe inflammatory reactions or high fever may occur, potentially causing a decrease in lymphocyte count. There might also be abnormal proliferation and differentiation of white blood cells. Patients should discontinue these medications under medical supervision and choose an appropriate treatment approach.

   3. Endocrine imbalance or immune system dysfunction

   A low lymphocyte count may result from endocrine imbalances or immune system disorders, such as HIV infection or acquired immunodeficiency syndrome (AIDS). Under medical guidance, medications such as spironolactone tablets, hydrocortisone tablets, or insulin injection may be used for treatment.

   In addition, viral infections can also cause low lymphocyte counts following radiotherapy. It is recommended that patients undergo regular blood tests during radiotherapy, ideally once a week. If significant bone marrow suppression is detected, radiotherapy should be stopped immediately.